JP3690703B2 - Cyanide ion concentration detection method - Google Patents

Description

【００１５】
表１の膜の極性の欄の＋，−は当該脂質を含む膜がプラス膜，マイナス膜であることを示す。
表１にもあるように、プラス膜とマイナス膜はそれぞれ複数種類があり、種類により味に対する応答に特徴がある。中には違う種類の膜でありながら、被測定溶液によって同じ応答をするものもあるが、複数種類の膜を用いれば１種類のときより味の情報を多く得られる。
【００１６】
各実施の形態を説明する前に、本発明のシアン化物イオンの濃度検出方法に用いるセンサ等と標準液について説明する。
本発明のシアン化物イオンの濃度検出方法に用いるセンサ等には、
▲１▼両親媒性物質を含む膜のうちプラス膜を用いたセンサ（以後、プラス膜センサという。）
▲２▼両親媒性物質を含む膜のうちマイナス膜を用いたセンサ（以後、マイナス膜センサという。）
▲３▼導電率計
があり、▲１▼プラス膜センサおよび▲２▼マイナス膜センサは、前述のように、用いる膜に種類があることから、それぞれ複数種類存在する。
【００１７】
したがって、本発明の方法に用いる組合せは、センサ等の数が少ない組合せとしては、
(1)プラス膜センサ１種類およびマイナス膜センサ１種類
(2)プラス膜センサ１種類および導電率計
(3)マイナス膜センサ１種類および導電率計
があり、物質のイオン濃度についてより多くの情報を加味するために、(1) 〜(3) のいずれかに、当該組合せに含まれていない種類の両親媒性物質を含む膜を用いたプラス膜センサおよびマイナス膜センサのうちの１種類または複数種類を加えた組合せがある。すなわち、
(4)プラス膜センサ１種類およびマイナス膜センサ複数種類
(5)プラス膜センサ複数種類およびマイナス膜センサ１種類
(6)プラス膜センサ複数種類およびマイナス膜センサ複数種類
(7)プラス膜センサ複数種類および導電率計
(8)マイナス膜センサ複数種類および導電率計
(9)プラス膜センサ１種類、マイナス膜センサ１種類、および導電率計
(10)プラス膜センサ複数種類、マイナス膜センサ複数種類、および導電率計
等である。
【００１８】
前述のセンサ等の各組合せに応じて、準備する標準液が異なる。
(1)プラス膜センサ１種類およびマイナス膜センサ１種類の場合は、
(a)ブランクサンプル液（シアン化物イオンの濃度検出の対象となる液と同種の液であって、かつ、シアン化物イオンの濃度が実質的に０％の液。具体的には、測定対象が工場排水なら、例えばその工場排水でシアン化物イオンの濃度が無視できるような状態のときのものをブランクサンプル液とする。あるいは、その組成が分かっていれば、同じ組成のものを作製する。）
(b)シアン標準液（シアン化物イオンの濃度が既知であり、かつ、その濃度が (a)ブランクサンプル液と異なる。具体的には、例えばブランクサンプル液にシアン化物を添加して作製する。）
(c)物質Ｂの標準液（使用するセンサが濃度依存性を持っているような物質Ｂ（例えば、ＫＣｌ）について既知の濃度であり、かつ、その濃度が (a)ブランクサンプル液と異なる。また、シアン化物イオンの濃度が実質的に０％の液。具体的には、例えばブランクサンプル液に物質Ｂを添加して作製する。）
【００１９】
(2)プラス膜センサ１種類および導電率計の場合と (3)マイナス膜センサ１種類および導電率計の場合は、
(a)ブランクサンプル液
(b)シアン標準液
(d)導電率標準液（導電率またはブランクサンプル液との導電率の差が既知であり、かつ、その導電率が (a)ブランクサンプル液と異なる。具体的には、例えばブランクサンプル液に導電率を変化させる物質を添加して作製する。）
である。
【００２０】
また、前述の (4)〜(10)のセンサ等の組合せのようにプラス膜センサまたはマイナス膜センサが増えた場合は、増えたセンサの種類ｎ分の物質Ｂ1,Ｂ2,・・・，Ｂn 各々の標準液が必要となる。該標準液はそれぞれ前記物質Ｂの標準液と同様に、使用するセンサが濃度依存性を持っているような物質Ｂ1,Ｂ2,・・・，Ｂn についてブランクサンプル液との差が既知の濃度であり、かつ、その濃度が (a)ブランクサンプル液と異なる。
【００２１】
なお、センサの種類を増やすと、標準液の種類も増え、その調製や測定、モデル式の決定、その後の被測定溶液の測定およびシアン化物イオン濃度の推定に手数がかかるが、シアン化物イオン以外の物質の濃度情報も加味されるので、シアン化物イオンの実際の濃度と推定値との相関は高くなる。他に、使用するセンサの種類は増やさず標準液の種類は増やして、使用するセンサの種類より２以上多い式を立て、重回帰分析にかけて各係数を求めるようにすれば、連立方程式を解いて得られた単一の解である係数よりも、多くの物質の濃度の変化に対して、対応できる係数が得られる。
また、モデル式を決定するための測定は、センサの種類を多くして行い、得られたデータを重回帰分析等にかけて、測定により有効なセンサを選ぶこととすれば、モデル式の決定以後の手数は軽減される。
【００２２】
ここで、本発明の方法の各段階の順序について説明すると、基準液他の各液を準備する段階ではどのような順番で準備してもよく、各液について測定を行うときに準備できていればよい。また、基準液以外の各液の測定順序も特に制限はなく、組になっている基準液の測定と他の各液の測定（例えば、段階（１）と段階（２）、段階（７）と段階（８）等）もどちらを先にしてもよい。なお、センサの測定安定度と要求されるイオン濃度推定精度との関係によっては、基準液の測定を毎回は行う必要はなく、あるいは、全く行わなくてもよい。
【００２３】
本発明の第一の実施の形態は、プラス膜センサ１種類とマイナス膜センサ１種類を用いたものであり、前述の (1)の場合に当たる。測定対象は工場排水とする。
１）１０ｍＭ（ｍ mol／ｌ）ＫＣｌ（塩化カリウム）溶液を基準液として準備する。また、基準液と同じ液を基準液用共洗い液として用意する。基準液用共洗い液は、基準液がセンサ等に付いている別の液等で汚れるのを防ぐために、基準液を測定する前に共洗いするための液である。１０ｍＭ（ｍ mol／ｌ）ＫＣｌ溶液は、センサに用いられている膜が乾燥してしまわないように、その保存液としても使われる。
２）シアン化物イオンが含まれていない工場排水をブランクサンプル液として準備する。また、ブランクサンプル液と同じ液をブランクサンプル液用共洗い液として用意する。
３）前記ブランクサンプル液と同じ液にシアン化物を加えシアン化物イオン濃度１ppm としたシアンサンプル標準液を準備する。シアン化物イオン濃度をここでは１ppm としたが、測定対象に応じて適宜決めればよい。また、シアンサンプル標準液と同じ液をシアンサンプル標準液用共洗い液として用意する。
４）前記ブランクサンプル液と同じ液に含まれる、使用するセンサが濃度依存性を有する物質Ｂを選び、該物質Ｂを前記ブランクサンプル液と同じ液に添加して、前記ブランクサンプル液との当該物質Ｂの濃度差が既知である物質Ｂ標準液を準備する。また、物質Ｂ標準液と同じ液を物質Ｂ標準液用共洗い液として用意する。この実施の形態で使用するセンサは２個であるから、物質Ｂは１種類選べばよい。物質Ｂはセンサの測定値に影響の大きい物質がよく、濃度依存性大のもの、混入量の変化が大きいもの、等である。
【００２４】
５）前記基準液を測定し、測定値Ｖkbを得る。
この実施の形態では、プラス膜センサとマイナス膜センサを各１個使用することとしている。それらのセンサを基準液用共洗い液に２〜１０回出し入れして、共洗いした後、基準液にセンサを浸漬しプラス膜センサの測定値ＶkbP とマイナス膜センサの測定値ＶkbM とを得る。
６）前記ブランクサンプル液を測定し、測定値Ｖbsを得る。
ブランクサンプル液用共洗い液に前記センサ２個を２〜１０回出し入れして、共洗いした後、ブランクサンプル液に両センサを浸漬し、両センサの測定値ＶbsP とＶbsM とを得る。
７）再び、前記基準液を測定し、測定値Ｖkcを得る。
基準液用共洗い液に両センサを２〜１０回出し入れして、共洗いした後、基準液に両センサを浸漬し、両センサの測定値ＶkcP とＶkcM とを得る。
８）前記シアンサンプル標準液を測定し、測定値Ｖcsを得る。
シアンサンプル標準液用共洗い液に両センサを２〜１０回出し入れして、共洗いした後、シアンサンプル標準液に両センサを浸漬し、両センサの測定値ＶcsP とＶcsM とを得る。
９）前記基準液を測定し、測定値Ｖk を得る。
基準液用共洗い液にセンサを２〜１０回出し入れして、共洗いした後、基準液に両センサを浸漬し、両センサの測定値ＶkPとＶkMとを得る。
１０）前記物質Ｂ標準液を測定し、測定値ＶB を得る。
物質Ｂ標準液用共洗い液に両センサを２〜１０回出し入れして、共洗いした後、物質Ｂ標準液に両センサを浸漬し、両センサの測定値ＶBPとＶBMとを得る。
【００２５】
１１）前記測定値Ｖbsと測定値Ｖkbとの差Ｖbsk ＝Ｖbs−Ｖkb、前記測定値Ｖcsと測定値Ｖkcとの差Ｖcsk ＝Ｖcs−Ｖkc、および前記測定値ＶB と前記測定値Ｖk との差ＶBk＝ＶB −Ｖk を求める。
これらをプラス膜センサとマイナス膜センサそれぞれについて行うから、差ＶbskP＝ＶbsP −ＶkbP 、差ＶcskP＝ＶcsP −ＶkcP 、差ＶBkP ＝ＶBP−ＶkP、差ＶbskM＝ＶbsM −ＶkbM 、差ＶcskM＝ＶcsM −ＶkcM 、および差ＶBkM ＝ＶBM−ＶkMが求まる。
１２）シアン化物イオンの濃度を推定するモデル式を決定する。
使用するセンサが２個であるから、モデル式は次のようになる。
シアン化物イオン濃度＝ａ1 Ｖs1＋ａ2 Ｖs2＋ｃ
このモデル式の各係数ａ1 ，ａ2 ，ｃを決定するために、１１）で求めた各値（差）を用いる。前述の各液毎に式が立てられ、式の左辺は、各液の注目する物質についてのイオン濃度となる。また、式の右辺のＶs1およびＶs2にはプラス膜センサ、はマイナス膜センサの各値（差）が代入される。この実施の形態では、
シアン化物イオン濃度０ppm ＝ａ1 ＶbskP＋ａ2 ＶbskM＋ｃ
シアン化物イオン濃度１ppm ＝ａ1 ＶcskP＋ａ2 ＶcskM＋ｃ
物質Ｂイオン濃度差 ppm ＝ａ1 ＶBkP ＋ａ2 ＶBkM ＋ｃ
の３つの式が立つ。この連立方程式を解いて、各係数ａ1 ，ａ2 ，ｃを決定する。
【００２６】
１３）前記基準液を測定し、測定値Ｖskh を得る。
基準液用共洗い液に両センサを２〜１０回出し入れして、共洗いした後、基準液に両センサを浸漬し、両センサの測定値ＶskhPとＶskhMとを得る。
１４）被測定サンプル液を測定し、測定値Ｖhsを得る。
被測定サンプル液と同じ液を被測定サンプル液用共洗い液として用いる。
被測定サンプル液用共洗い液に両センサを２〜１０回出し入れして、共洗いした後、被測定サンプル液に両センサを浸漬し、両センサの測定値ＶhsP とＶhsM とを得る。
１５）前記測定値Ｖhsと測定値Ｖskh との差Ｖhsk ＝Ｖhs−Ｖskh を求める。
これらをプラス膜センサとマイナス膜センサそれぞれについて行うから、差ＶhskP＝ＶhsP −ＶskhPと差ＶhskM＝ＶhsM −ＶskhMとが求まる。
１６）１５）で求めた各値（差）を各係数が決定した前記モデル式に代入して、前記被測定サンプル液のシアン化物イオンの濃度を推定する。すなわち、被測定サンプル液のシアン化物イオンの濃度は、
シアン化物イオン濃度＝ａ1 ＶhskP＋ａ2 ＶhskM＋ｃ
と推定される。
本実施の形態では、各液について２個のセンサで同時に測定しているが、１個ずつ測定することとしてもよい。
【００２７】
本発明の第二の実施の形態は、プラス膜センサ２種類とマイナス膜センサ２種類と導電率計を用いたものであり、前述の(10)プラス膜センサ複数種類、マイナス膜センサ複数種類、および導電率計の場合に当たる。測定対象は、第一の実施の形態の場合と同じく、工場排水とする。
１）１０ｍＭ（ｍ mol／ｌ）ＫＣｌ（塩化カリウム）溶液を基準液として準備する。また、基準液と同じ液を基準液用共洗い液として用意する。
２）シアン化物イオンが含まれていない工場排水をブランクサンプル液として準備する。また、ブランクサンプル液と同じ液をブランクサンプル液用共洗い液として用意する。
３）前記ブランクサンプル液と同じ液にシアン化物を加えシアン化物イオン濃度１０ppm としたシアンサンプル標準液を準備する。また、シアンサンプル標準液と同じ液をシアンサンプル標準液用共洗い液として用意する。
４）前記ブランクサンプル液と同じ液に含まれる、使用するセンサが濃度依存性を有する物質Ｂ1 ，Ｂ2 ，Ｂ3 を選び、該物質Ｂ1 ，Ｂ2 ，Ｂ3 を前記ブランクサンプル液と同じ液にそれぞれ添加して、前記ブランクサンプル液との当該物質Ｂ1 ，Ｂ2 ，Ｂ3 の濃度差が既知である物質Ｂ1 標準液、物質Ｂ2 標準液、および物質Ｂ3 標準液を準備する。また、物質Ｂ1 標準液、物質Ｂ2 標準液、および物質Ｂ3 標準液と同じ液をそれぞれ物質Ｂ1 標準液用共洗い液、物質Ｂ2 標準液用共洗い液、および物質Ｂ3 標準液用共洗い液として用意する。この実施の形態で使用するセンサは４個であるから、物質Ｂは３種類選ぶことになる。
さらに、導電率計を使用するので、前記ブランクサンプル液と同じ液に例えばＫＣｌを加えてその導電率を変えた導電率標準液を準備する。そして、導電率標準液と同じ液を標準液用共洗い液としても用意する。
【００２８】
５）前記基準液を測定し、測定値Ｖkbを得る。
この実施の形態では、プラス膜センサとマイナス膜センサを各２個それに導電率計を使用することとしている。それらのセンサ等を基準液用共洗い液に２〜１０回出し入れして、共洗いした後、基準液にセンサ等を浸漬し２個のプラス膜センサの測定値ＶkbP1，ＶkbP2と、２個のマイナス膜センサの測定値ＶkbM1，ＶkbM2と、導電率計の測定値Ｖkbd とを得る。
６）前記ブランクサンプル液を測定し、測定値Ｖbsを得る。
ブランクサンプル液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、ブランクサンプル液にセンサ等を浸漬し、各センサ等の測定値ＶbsP1，ＶbsP2，ＶbsM1，ＶbsM2，Ｖbsd を得る。
７）再び、前記基準液を測定し、測定値Ｖkcを得る。
基準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、基準液に浸漬し、各センサ等の測定値ＶkcP1，ＶkcP2，ＶkcM1，ＶkcM2，Ｖkcd を得る。
８）前記シアンサンプル標準液を測定し、測定値Ｖcsを得る。
シアンサンプル標準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、シアンサンプル標準液に浸漬し、各センサ等の測定値ＶcsP1，ＶcsP2，ＶcsM1，ＶcsM2，Ｖcsd を得る。
【００２９】
９−１）前記基準液を測定し、測定値Ｖk を得る。
基準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、基準液に浸漬し、各センサ等の測定値Ｖk1P1，Ｖk1P2，Ｖk1M1，Ｖk1M2，Ｖk1d を得る。
１０−１）前記物質Ｂ標準液を測定し、測定値ＶB を得る。
物質Ｂ1 標準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、物質Ｂ1 標準液に浸漬し、各センサ等の測定値ＶB1P1，ＶB1P2，ＶB1M1，ＶB1M2，ＶB1d を得る。
９−２）前記基準液を測定し、測定値Ｖk を得る。
基準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、基準液に浸漬し、各センサ等の測定値Ｖk2P1，Ｖk2P2，Ｖk2M1，Ｖk2M2，Ｖk2d を得る。
１０−２）前記物質Ｂ標準液を測定し、測定値ＶB を得る。
物質Ｂ2 標準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、物質Ｂ2 標準液に浸漬し、各センサ等の測定値ＶB2P1，ＶB2P2，ＶB2M1，ＶB2M2，ＶB2d を得る。
９−３）前記基準液を測定し、測定値Ｖk を得る。
基準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、基準液に浸漬し、各センサ等の測定値Ｖk3P1，Ｖk3P2，Ｖk3M1，Ｖk3M2，Ｖk3d を得る。
１０−３）前記物質Ｂ標準液を測定し、測定値ＶB を得る。
物質Ｂ3 標準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、物質Ｂ3 標準液に浸漬し、各センサ等の測定値ＶB3P1，ＶB3P2，ＶB3M1，ＶB3M2，ＶB3d を得る。
９−４）前記基準液を測定し、測定値Ｖkdを得る。
基準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、基準液に浸漬し、各センサ等の測定値ＶkdP1，ＶkdP2，ＶkdM1，ＶkdM2，Ｖkdd を得る。
１０−４）前記物質Ｂ標準液を測定し、測定値Ｖd を得る。
導電率標準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、導電率標準液に浸漬し、各センサ等の測定値ＶdP1 ，ＶdP2 ，ＶdM1 ，ＶdM2 ，Ｖddを得る。
【００３０】
１１）前記測定値Ｖbsと測定値Ｖkbとの差Ｖbsk ＝Ｖbs−Ｖkb、前記測定値Ｖcsと測定値Ｖkcとの差Ｖcsk ＝Ｖcs−Ｖkc、前記測定値ＶB と前記測定値Ｖk との差ＶBk＝ＶB −Ｖk （ただし、この実施の形態では物質Ｂ1 ，物質Ｂ2 ，物質Ｂ3 の標準液を用いるので、差ＶBkについては、差ＶBk1 ＝ＶB1−Ｖk1，差ＶBk2 ＝ＶB2−Ｖk2，および差ＶBk3 ＝ＶB3−Ｖk3）、および前記測定値Ｖd と前記測定値Ｖkdとの差Ｖdk＝Ｖd −Ｖkdを求める。
これらをプラス膜センサ２個、マイナス膜センサ２個、および導電率計の測定値それぞれについて行うから、
差ＶbskP1 ＝ＶbsP1−ＶkbP1、差ＶcskP1 ＝ＶcsP1−ＶkcP1、
差ＶBk1P1 ＝ＶB1P1−Ｖk1P1、差ＶBk2P1 ＝ＶB2P1−Ｖk2P1、
差ＶBk3P1 ＝ＶB3P1−Ｖk3P1、差ＶdkP1＝ＶdP1 −ＶkdP1、
差ＶbskP2 ＝ＶbsP2−ＶkbP2、差ＶcskP2 ＝ＶcsP2−ＶkcP2、
差ＶBk1P2 ＝ＶB1P2−Ｖk1P2、差ＶBk2P2 ＝ＶB2P2−Ｖk2P2、
差ＶBk3P2 ＝ＶB3P2−Ｖk3P2、差ＶdkP2＝ＶdP2 −ＶkdP2、
差ＶbskM1 ＝ＶbsM1−ＶkbM1、差ＶcskM1 ＝ＶcsM1−ＶkcM1、
差ＶBk1M1 ＝ＶB1M1−Ｖk1M1、差ＶBk2M1 ＝ＶB2M1−Ｖk2M1、
差ＶBk3M1 ＝ＶB3M1−Ｖk3M1、差ＶdkM1＝ＶdM1 −ＶkdM1、
差ＶbskM2 ＝ＶbsM2−ＶkbM2、差ＶcskM2 ＝ＶcsM2−ＶkcM2、
差ＶBk1M2 ＝ＶB1M2−Ｖk1M2、差ＶBk2M2 ＝ＶB2M2−Ｖk2M2、
差ＶBk3M2 ＝ＶB3M2−Ｖk3M2、差ＶdkM2＝ＶdM2 −ＶkdM2、
差Ｖbskd＝Ｖbsd −Ｖkbd 、 差Ｖcskd＝Ｖcsd −Ｖkcd 、
差ＶBk1d＝ＶB1d −Ｖk1d 、 差ＶBk2d＝ＶB2d −Ｖk2d 、
差ＶBk3d＝ＶB3d −Ｖk3d 、 差Ｖdkd ＝Ｖdd −Ｖkdd 、
が求まる。
【００３１】
１２）シアン化物イオンの濃度を推定するモデル式を決定する。
使用するセンサ等が５個であるから、モデル式は次のようになる。
シアン化物イオン濃度＝ａ1 Ｖs1＋ａ2 Ｖs2＋ａ3 Ｖs3＋ａ4 Ｖs4＋ａ5 Ｖs5＋ｃ
このモデル式の各係数ａ1 ，ａ2 ，ａ3 ，ａ4 ，ａ5 ，ｃを決定するために、１１）で求めた各値（差）を用いる。前述の各液毎に式が立てられ、式の左辺は、各液の注目する物質についてのイオン濃度等となる。また、式の右辺のＶs1，Ｖs2，Ｖs3，Ｖs4，Ｖs5にはセンサ等の各値（差）が代入される。この実施の形態では、
シアン化物イオン濃度０ppm ＝ａ1 ＶbskP1 ＋ａ2 ＶbskP2 ＋ａ3 ＶbskM1 ＋ａ4 ＶbskM2 ＋ａ5 Ｖbskd＋ｃ
シアン化物イオン濃度10ppm ＝ａ1 ＶcskP1 ＋ａ2 ＶcskP2 ＋ａ3 ＶcskM1 ＋ａ4 ＶcskM2 ＋ａ5 Ｖcskd＋ｃ
物質Ｂ1 イオン濃度差 ppm ＝ａ1 ＶBk1P1 ＋ａ2 ＶBk1P2 ＋ａ3 ＶBk1M1 ＋ａ4 ＶBk1M2 ＋ａ5 ＶBk1d＋ｃ
物質Ｂ2 イオン濃度差 ppm ＝ａ1 ＶBk2P1 ＋ａ2 ＶBk2P2 ＋ａ3 ＶBk2M1 ＋ａ4 ＶBk2M2 ＋ａ5 ＶBk2d＋ｃ
物質Ｂ3 イオン濃度差 ppm ＝ａ1 ＶBk3P1 ＋ａ2 ＶBk3P2 ＋ａ3 ＶBk3M1 ＋ａ4 ＶBk3M2 ＋ａ5 ＶBk3d＋ｃ
導電率 ＝ａ1 ＶdkP1 ＋ａ2 ＶdkP2 ＋ａ3 ＶdkM1 ＋ａ4 ＶdkM2 ＋ａ5 Ｖdkd ＋ｃ
の６つの式が立つ。この連立方程式を解いて、各係数ａ1 ，ａ2 ，ａ3 ，ａ4 ，ａ5 ，ｃを決定する。
【００３２】
１３）前記基準液を測定し、測定値Ｖskh を得る。
基準液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、基準液に浸漬し、各センサ等の測定値ＶskhP1 ，ＶskhP2 ，ＶskhM1 ，ＶskhM2 ，Ｖskhdを得る。
１４）被測定サンプル液を測定し、測定値Ｖhsを得る。
被測定サンプル液と同じ液を被測定サンプル液用共洗い液として用いる。
被測定サンプル液用共洗い液に前記センサ等を２〜１０回出し入れして、共洗いした後、被測定サンプル液に浸漬し、各センサ等の測定値ＶhsP1，ＶhsP2，ＶhsM1，ＶhsM2，Ｖhsd を得る。
１５）前記測定値Ｖhsと測定値Ｖskh との差Ｖhsk ＝Ｖhs−Ｖskh を求める。
これらをプラス膜センサ２個、マイナス膜センサ２個、および導電率計の測定値それぞれについて行うから、差ＶhskP1 ＝ＶhsP1−ＶskhP1 ，差ＶhskP2 ＝ＶhsP2−ＶskhP2 ，差ＶhskM1 ＝ＶhsM1−ＶskhM1 ，差ＶhskM2 ＝ＶhsM2−ＶskhM2 ，差Ｖhskd ＝Ｖhsd −Ｖskhdが求まる。
１６）１５）で求めた各値（差）を各係数が決定した前記モデル式に代入して、前記被測定サンプル液のシアン化物イオンの濃度を推定する。すなわち、被測定サンプル液のシアン化物イオンの濃度は、
シアン化物イオン濃度＝ａ1 ＶhskP1 ＋ａ2 ＶhskP2 ＋ａ3 ＶhskM1 ＋ａ4 ＶhskM2 ＋ａ5 Ｖhskd＋ｃ
と推定される。
【００３３】
表２に、本発明のシアン化物イオンの濃度検出方法を用いてシアン化物イオンの濃度が既知の被測定溶液を測定し、得られたシアン化物イオン濃度の推定値と実際の濃度との相関の高さを示す。プラス膜センサ、マイナス膜センサ、導電率計の欄の丸印は、測定に用いたセンサ等である。
表２から分かるように、相関はかなり高い。
【００３４】
【表２】

【００３５】
【発明の効果】
本発明によれば、プラス膜を用いたセンサ、マイナス膜を用いたセンサ、および導電率計のうち少なくとも二つを組み合わせて測定することとし、適当な標準液を準備し、該標準液の測定値を用いてモデル式を求め、シアン化物イオンの濃度を推定することとしたから、
従来のシアン化物イオンの濃度測定法である分析法のような被測定液の予備処理を必要とせず、シアン化物イオン電極を用いる方法のような液温の調節も必要としない、シアン化物イオンの濃度の測定が短時間で簡単にできるシアン化物イオンの濃度検出方法が提供できる。
また、本発明のシアン化物イオンの濃度検出方法を用いれば、工場排水等の常時監視も容易になる。
【図面の簡単な説明】
【図１】本発明のシアン化物イオンの濃度検出方法の流れ図である。
【図２】本発明のシアン化物イオンの濃度検出方法の流れ図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for detecting a cyanide ion in a solution by using a sensor using a film containing an amphiphilic substance so that the concentration can be estimated.
For example, the present invention relates to a technique that enables continuous monitoring of wastewater from a factory using cyanide such as a plating factory.
[0002]
[Prior art]
Conventionally, the concentration of cyanide ions in factory effluent and the like has been determined by analytical methods such as the pyridine-pyrazolone method and the silver nitrate method and measurement methods using a cyanide ion electrode.
The pyridine-pyrazolone method is a widely used method for analyzing cyanate wastewater. In this test method, the test solution absorbed in the sodium hydroxide solution by the pretreatment is neutralized with acetic acid, and then chloramine T solution is added to form cyan chloride. To this, a pyridine-pyrazolone mixture is added, and the resulting blue light is absorbed. It is a method of measuring by a photometric method.
The silver nitrate method is used for high concentrations. The determination range is suitable when the cyan concentration is 1 ppm or more. Titrate with 1 / 100N silver nitrate solution using p-dimethylaminobenzylidene rhodanine acetone solution as an indicator. The end point is the point at which the color of the liquid changes from yellow to red, and the cyan ion concentration is calculated from the required drop constant. Since the reaction varies depending on the pH, it must be titrated to pH 11.0 or higher.
[0003]
[Problems to be solved by the invention]
When using an analytical method, it is necessary to prepare various kinds of reagents as described above and to perform pretreatment for removal of interfering substances. When using a cyanide ion electrode, the potential fluctuates due to changes in the liquid temperature. It is necessary to adjust the liquid temperature of the sample within ± 1 ° C. of the liquid temperature at the time of preparing the calibration curve, and the concentration of cyanide ions cannot be measured easily.
[0004]
An object of the present invention is to provide a cyanide ion concentration detection method capable of easily measuring the cyanide ion concentration in a short time. In addition, for example, for continuous monitoring of water quality at the intake of a water purification plant, conventionally, a plurality of aquariums are provided from upstream to downstream of the wastewater, and when toxic substances flow, fish move from the upstream aquarium to the downstream aquarium. However, this method is usually difficult to maintain reliability, such as learning that the fish is in the upstream aquarium or paying attention to the physical condition of the fish. Become. An object of the present invention is to provide a cyanide ion concentration detection method capable of constantly monitoring factory effluent or the like instead of such a conventional method.
[0005]
[Means for Solving the Problems]
For example, a potential response of a film containing an amphiphile is similar to a human taste organ with respect to taste, and a sensor using this film is called a taste sensor. Since the taste sensor is not a sensor selectively sensitive to a specific substance, the taste or the difference in taste is measured from the responses of a plurality of types of taste sensors.
[0006]
The inventors of the present invention confirmed that a sensor using a film containing an amphiphile responds according to the concentration of cyanide ions, and the film containing an amphiphile is a hydrophilic group of the amphiphile contained in the film. Depending on the charge of the film, there are a film (hereinafter referred to as a positive film) in which the charge on the film surface is positive, and a film (hereinafter referred to as a negative film) in which the charge is negative. It was found that the concentration of cyanide ions can be estimated by measuring a standard solution and building a model equation prior to measurement of the solution to be measured. In addition, a model formula can also be established to measure cyanide ions by combining a sensor using a plus membrane or a sensor using a minus membrane and a conductivity meter (hereinafter collectively referred to as a sensor). It was found that the concentration of can be estimated. The present invention is based on these findings.
[0007]
In order to solve the above-mentioned problem, the cyanide ion concentration detection method of the present invention comprises:
A method for detecting the concentration of cyanide ions using a sensor using a film containing an amphiphile, comprising a step of preparing a reference solution and a solution of the same type as a solution whose concentration is to be detected. And a step of preparing a blank sample solution having a cyanide ion concentration of substantially 0%, a solution obtained by adding cyanide to a liquid of the same type as the blank sample solution, and containing cyanide ions A step of preparing a cyan sample standard solution having a known concentration, and N-1 types of sensors to be used, which are contained in the same type of liquid as the blank sample solution, which is one less than the type N of sensors to be used, have concentration dependency. Each substance B1, B2,..., BN-1 each substance Bi (i is any one of 1, 2,..., N-1) standard solution and the blank sample solution Of the substance Bi A step of preparing a standard solution of the substance Bi (i = 1, 2,..., N-1) having a known degree of difference, a step (1) of obtaining a measured value Vkb of the reference solution, and the blank sample A step (2) of obtaining a measured value Vbs of the liquid, a step (3) of obtaining a measured value Vkc of the reference solution, a step (4) of obtaining the measured value Vcs of the cyan sample standard solution, and the measurement of the reference solution And the measurement of the substance Bi (i = 1, 2,..., N-1) standard solution alternately, and the measured value Vki (i = 1, 2,..., N-) of the reference solution. (1) and obtaining the measured values VBi (i = 1, 2,..., N-1) of the standard solution of the substance Bi (i = 1, 2,..., N-1) (5) And the difference Vbsk = Vbs−Vkb between the measured value Vbs and the measured value Vkb, the difference Vcsk = Vcs−Vkc between the measured value Vcs and the measured value Vkc, the measured value VBi (i = 1, 2,... , N-1) and A step (6) of obtaining a difference VBki = VBi−Vki (i = 1, 2,..., N−1) from the measured value Vki (i = 1, 2,..., N−1); The steps (1) to (6) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. Then, a total of N sensors each including one or more sensors each using a membrane having a negative hydrophilic group charge of the amphiphile are obtained, and the difference Vbsk, Vcsk, VBki (i = 1, 2, ..., N-1), a model equation for estimating the concentration of cyanide ions
Cyanide ion concentration = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
, AN, c, a step (7) for obtaining the measured value Vskh of the reference liquid, and a step (8) for obtaining the measured value Vhs of the sample liquid to be measured. The step (9) for obtaining the difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh and the steps (7) to (9) are films containing an amphiphile and the parents Among the sensors using a membrane having a positive hydrophilic group charge of an amphiphile and a membrane containing an amphiphile and using a membrane having a negative hydrophilic group charge of the amphiphile, the model The difference Vs1, Vs2,..., VsN obtained for each coefficient is substituted into the model expression determined by each coefficient, and the measured sample solution is measured. And estimating the concentration of cyanide ions.
[0008]
Further, the cyanide ion concentration detection method of the present invention in combination with a conductivity meter,
A method for detecting the concentration of cyanide ions using a sensor using a film containing an amphiphile, comprising a step of preparing a reference solution and a solution of the same type as a solution whose concentration is to be detected. And a step of preparing a blank sample solution having a cyanide ion concentration of substantially 0%, a solution obtained by adding cyanide to a liquid of the same type as the blank sample solution, and containing cyanide ions A step of preparing a cyan sample standard solution having a known concentration, and N-2 types of sensors to be used, which are contained in the same kind of liquid as the blank sample solution, which is one less than the type of sensor N-1 to be used, are concentration-dependent. Each of the substances B1, B2,..., BN-2 having a property is a standard solution of each substance Bi (i is any one of 1, 2,..., N-2) and the blank. The substance Bi with sample liquid The substance Bi (i = 1, 2,..., N-2) standard solution having a known concentration difference, and the same kind of liquid as the blank sample solution, and the conductivity is different from that of the blank sample solution. And preparing a conductivity standard solution having a known difference between the conductivity or the conductivity of the blank sample solution, obtaining a measurement value Vkb of the reference solution (1), and measuring the blank sample solution Obtaining a value Vbs (2), obtaining a measured value Vkc of the reference solution (3), obtaining a measured value Vcs of the cyan sample standard solution (4), measuring the reference solution and the substance Bi (i = 1, 2,..., N-2) The standard solution and the conductivity standard solution are alternately measured, and the measured value Vki (i = 1, 2,...) Of the reference solution. , N-2) and Vkd and the substance Bi (i = 1, 2,..., N-2) standard solutions. Step (5) of obtaining a value VBi (i = 1, 2,..., N-2) and a measured value Vd of the conductivity standard solution, and a difference Vbsk = Vbs between the measured value Vbs and the measured value Vkb −Vkb, difference between the measured value Vcs and the measured value Vkc Vcsk = Vcs−Vkc, the measured value VBi (i = 1, 2,..., N−2) and the measured value Vki (i = 1,2) ,..., N-2) VBki = VBi-Vki (i = 1, 2,..., N-2) and the difference between the measured value Vd and the measured value Vkd Vdk = Vd-Vkd And a sensor using a film containing an amphiphile, wherein the hydrophilic group of the amphiphile has a positive charge, and A sensor including an amphiphile and having a negative charge on the hydrophilic group of the amphiphile is combined with one or more sensors and a conductivity meter. The difference Vbsk obtained for each, Vcsk, VBki (i = 1,2, ···, N-2), using a Vdk, model formula for estimating the concentration of cyanide ions
Cyanide ion concentration = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
, AN, c, a step (7) for obtaining the measured value Vskh of the reference liquid, and a step (8) for obtaining the measured value Vhs of the sample liquid to be measured. The step (9) for obtaining the difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh and the steps (7) to (9) are films containing an amphiphile and the parents Of the sensor using a membrane having a positive charge of the hydrophilic group of the amphiphile and a membrane containing an amphiphile and using a membrane having a negative charge of the hydrophilic group of the amphiphile, the model formula , VsN obtained by determining the coefficients Vs1, Vs2,..., VsN are substituted into the model equations determined by the respective coefficients, From the stage of estimating the cyanide ion concentration in the sample liquid It has become.
[0009]
The cyanide ion concentration detection method of the present invention using M kinds of substances Bi (i = 1, 2,..., M) standard solution,
A method for detecting the concentration of cyanide ions using a sensor using a film containing an amphiphile, comprising a step of preparing a reference solution and a solution of the same type as a solution whose concentration is to be detected. And a step of preparing a blank sample solution having a cyanide ion concentration of substantially 0%, a solution obtained by adding cyanide to a liquid of the same type as the blank sample solution, and containing cyanide ions A step of preparing a cyan sample standard solution having a known concentration, and each of the substances having the concentration dependency of the sensor to be used, which is included in the same kind of liquid as the blank sample solution, and which has M types of sensors to be used. B 1, B 2,..., B M Each substance Bi (i is any one of 1, 2,..., M) is a standard solution and the concentration of the substance Bi with the blank sample solution. The difference is known Preparing a standard solution of the substance Bi (i = 1, 2,..., M), obtaining a measured value Vkb of the reference solution (1), and obtaining a measured value Vbs of the blank sample solution (2), obtaining a measured value Vkc of the reference solution (3), obtaining a measured value Vcs of the cyan sample standard solution (4), measuring the reference solution, and the substance Bi (i = 1) , 2,..., M) Each measurement of the standard solution is alternately performed, and the measured value Vki (i = 1, 2,..., M) of the reference solution and the substance Bi (i = 1, 2, 1). ,..., M) Step (5) for obtaining each measured value VBi (i = 1, 2,..., M) of the standard solution and the difference between the measured value Vbs and the measured value Vkb Vbsk = Vbs -Vkb, difference between the measured value Vcs and the measured value Vkc Vcsk = Vcs-Vkc, the measured value VBi (i = 1, 2,..., M) and the measured value Vki (i = 1, 2,. .., M) The step (6) for obtaining the difference VBki = VBi-Vki (i = 1, 2,..., M) and the step (1) to the step (6) are films containing an amphiphile. And a sensor using a membrane having a positive charge of the hydrophilic group of the amphiphile and a membrane containing a film having a negative charge of the hydrophilic group of the amphiphile 1 A model formula for estimating the concentration of cyanide ions using the difference Vbsk, Vcsk, VBki (i = 1, 2,..., M) obtained for each of N in total.
Cyanide ion concentration = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
, AN, c, a step (7) for obtaining the measured value Vskh of the reference liquid, and a step (8) for obtaining the measured value Vhs of the sample liquid to be measured. The step (9) for obtaining the difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh and the steps (7) to (9) are films containing an amphiphile and the parents Among the sensors using a membrane having a positive hydrophilic group charge of an amphiphile and a membrane containing an amphiphile and using a membrane having a negative hydrophilic group charge of the amphiphile, the model The difference Vs1, Vs2,..., VsN obtained for each coefficient is substituted into the model expression determined by each coefficient, and the measured sample solution is measured. And estimating the concentration of cyanide ions.
[0010]
The method for detecting the concentration of cyanide ions according to the present invention using M kinds of substances Bi (i = 1, 2,..., M) standard solution and combining with a conductivity meter,
A method for detecting the concentration of cyanide ions using a sensor using a film containing an amphiphile, comprising a step of preparing a reference solution and a solution of the same type as a solution whose concentration is to be detected. And a step of preparing a blank sample solution having a cyanide ion concentration of substantially 0%, a solution obtained by adding cyanide to a liquid of the same type as the blank sample solution, and containing cyanide ions A step of preparing a cyan sample standard solution having a known concentration, and M types of sensors to be used, which are included in the same type of liquid as the blank sample solution, are N-1 or more types of sensors to be used have concentration dependency. Each material B1, B2,..., BM Each material Bi (i is any one of 1, 2,..., M) is a standard solution and the material Bi with the blank sample solution. Known concentration difference The substance Bi (i = 1, 2,..., M) standard solution, and the same kind of liquid as the blank sample solution, the conductivity is different from that of the blank sample solution, and the conductivity or blank sample. Preparing a conductivity standard solution whose difference from the conductivity of the solution is known, obtaining a measured value Vkb of the reference solution (1), and obtaining a measured value Vbs of the blank sample solution (2) Obtaining the measured value Vkc of the reference solution (3), obtaining the measured value Vcs of the cyan sample standard solution (4), measuring the reference solution and the substance Bi (i = 1, 2, .., M) Measurements of the standard solution and the conductivity standard solution are alternately performed, and the measured values Vki (i = 1, 2,..., M) and Vkd of the reference solution and the substance Bi ( i = 1, 2,..., M) Standard measurement values VBi (i = 1, 2,..., M) And obtaining a measured value Vd of the conductivity standard solution (5), a difference Vbsk = Vbs−Vkb between the measured value Vbs and the measured value Vkb, and a difference Vcsk = Vcs between the measured value Vcs and the measured value Vkc. −Vkc, difference between the measured value VBi (i = 1, 2,..., M) and the measured value Vki (i = 1, 2,..., M) VBki = VBi−Vki (i = 1) , 2,..., M) and the step (6) for obtaining the difference Vdk = Vd−Vkd between the measured value Vd and the measured value Vkd, and the steps (1) to (6). A film containing a hydrophilic substance, a film using a film having a positive hydrophilic group charge of the amphiphile, and a film containing an amphiphilic substance, wherein the hydrophilic group charge of the amphiphilic substance is negative. A total of N-1 sensors and a conductivity meter are combined with a sensor using a membrane, and the difference Vbsk, Vcsk, Bki (i = 1,2, ···, M), with Vdk, model formula for estimating the concentration of cyanide ions
Cyanide ion concentration = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
, AN, c, a step (7) for obtaining the measured value Vskh of the reference liquid, and a step (8) for obtaining the measured value Vhs of the sample liquid to be measured. The step (9) for obtaining the difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh and the steps (7) to (9) are films containing an amphiphile and the parents Of the sensor using a membrane having a positive charge of the hydrophilic group of the amphiphile and a membrane containing an amphiphile and using a membrane having a negative charge of the hydrophilic group of the amphiphile, the model formula , VsN obtained by determining the coefficients Vs1, Vs2,..., VsN are substituted into the model equations determined by the respective coefficients, From the stage of estimating the cyanide ion concentration in the sample liquid It has become.
[0011]
[Action]
In the case of using the cyanide ion concentration detection method of the present invention, once the model formula is determined, the normal measurement may be performed after step (7).
[0012]
For example, each coefficient of the model formula is determined as follows.
Cyanide ion concentration = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
The left side shows the cyanide ion concentration of the blank sample solution (ie, 0 ppm) for the measurement of the blank sample solution, the cyanide ion concentration of the cyan sample standard solution for the measurement of the cyan sample standard solution, and the substance for the measurement of the substance Bi standard solution. Substitute the difference in Bi ion concentration with the blank sample solution and the conductivity standard solution with the difference in conductivity or conductivity with the blank sample solution, the right side is the measured value of each solution corresponding to the left side, and Vs1 The value obtained from the sensor 1 is substituted for Vs2, the value obtained from the sensor 2 is substituted for Vs2, and the value obtained from the sensor N (or conductivity meter) is substituted for VsN.
as a result,
Cyanide ion concentration 0ppm = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Cyanide ion concentration 1ppm = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Substance B1 Ion concentration difference = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Substance B2 Ion concentration difference = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
・ ・ ・
・ ・ ・
Substance BN Ion concentration difference (or conductivity) = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Get. Solve these simultaneous equations to find each coefficient.
In addition, when there are M types of substance Bi standard solutions and an equation more than two is larger than the number of coefficients, each coefficient is obtained by, for example, multiple regression analysis.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
As described above, the cyanide ion concentration detection method of the present invention uses a sensor using a film containing an amphiphile. Here, an example of the amphiphilic substance is shown in Table 1.
Table 1 also lists lipids, which are a kind of amphiphile, but sensors using lipid membranes containing lipids are also called lipid membrane sensors.
[0014]
[Table 1]

[0015]
+ And − in the column of membrane polarity in Table 1 indicate that the membrane containing the lipid is a plus membrane or a minus membrane.
As shown in Table 1, there are a plurality of types of plus membranes and minus membranes, and the response to taste is characterized by the types. Some of the membranes are different types but have the same response depending on the solution to be measured. However, if a plurality of types of membranes are used, more taste information can be obtained than with one type.
[0016]
Before describing each embodiment, a sensor and the like used in the cyanide ion concentration detection method of the present invention and a standard solution will be described.
The sensor used in the cyanide ion concentration detection method of the present invention includes:
(1) Sensor using a plus membrane among membranes containing amphiphiles (hereinafter referred to as a plus membrane sensor)
(2) A sensor using a minus membrane among membranes containing amphiphiles (hereinafter referred to as minus membrane sensor)
(3) Conductivity meter
There are two types of (1) plus membrane sensor and (2) minus membrane sensor, since there are types of membranes to be used as described above.
[0017]
Therefore, the combination used in the method of the present invention is a combination with a small number of sensors,
(1) One plus membrane sensor and one minus membrane sensor
(2) One type of positive membrane sensor and conductivity meter
(3) One type of negative membrane sensor and conductivity meter
In order to take into account more information about the ion concentration of the substance, any of (1) to (3) plus a film using a film containing an amphiphilic substance of a type not included in the combination. There are combinations of one or more of membrane sensors and minus membrane sensors. That is,
(4) One plus membrane sensor and several minus membrane sensors
(5) Plural types of positive membrane sensors and one type of negative membrane sensors
(6) Multiple types of positive membrane sensors and multiple types of negative membrane sensors
(7) Plural types of membrane sensors and conductivity meter
(8) Multiple types of negative membrane sensors and conductivity meter
(9) One plus membrane sensor, one minus membrane sensor, and conductivity meter
(10) Multiple types of positive membrane sensors, multiple types of negative membrane sensors, and conductivity meter
Etc.
[0018]
The standard solution to be prepared differs depending on the combination of the sensors and the like.
(1) For one type of plus membrane sensor and one type of minus membrane sensor,
(a) Blank sample liquid (liquid of the same kind as the liquid whose concentration of cyanide ions is to be detected, and having a cyanide ion concentration of substantially 0%. If it is a factory wastewater, for example, the one in a state where the concentration of cyanide ions in the factory wastewater can be ignored is used as a blank sample solution, or if the composition is known, the same composition is prepared.)
(b) Cyan standard solution (concentration of cyanide ions is known and the concentration is different from (a) blank sample solution. Specifically, for example, cyanide is added to the blank sample solution. )
(c) Standard solution of substance B (concentration known for substance B (for example, KCl) for which the sensor used has concentration dependence), and the concentration is different from (a) blank sample solution. In addition, a solution having a cyanide ion concentration of substantially 0%, specifically prepared by adding the substance B to a blank sample solution, for example.
[0019]
(2) For one type of positive membrane sensor and conductivity meter, and (3) For one type of negative membrane sensor and conductivity meter,
(a) Blank sample solution
(b) Cyan standard solution
(d) Conductivity standard solution (conductivity or conductivity difference with blank sample solution is known and its conductivity is different from (a) blank sample solution. It is made by adding a substance that changes conductivity.)
It is.
[0020]
Further, when the number of plus membrane sensors or minus membrane sensors increases as in the combination of the sensors (4) to (10) described above, substances B1, B2,. Each standard solution is required. Each of the standard solutions is similar to the standard solution of substance B, and the difference between the substance B1, B2,. Yes, and its concentration is different from (a) blank sample solution.
[0021]
Increasing the number of types of sensors increases the number of types of standard solutions, and it takes time to prepare and measure them, determine model formulas, and then measure the solution to be measured and estimate the cyanide ion concentration. Therefore, the correlation between the actual cyanide ion concentration and the estimated value is high. In addition, the number of sensors to be used is not increased, the number of types of standard solutions is increased, and two or more equations are set up than the types of sensors to be used, and each coefficient is calculated by multiple regression analysis. The coefficient which can respond to the change of the density | concentration of many substances is obtained rather than the coefficient which is the obtained single solution.
In addition, the measurement to determine the model formula is performed by increasing the number of types of sensors, and the obtained data is subjected to multiple regression analysis etc. Time is reduced.
[0022]
Here, the order of each step of the method of the present invention will be described. In the step of preparing the reference solution and other liquids, they may be prepared in any order, and may be prepared when measuring each liquid. That's fine. In addition, the order of measurement of each liquid other than the reference liquid is not particularly limited, and the measurement of the reference liquid and the measurement of each other liquid (for example, step (1), step (2), step (7)) And step (8) etc.) may be performed first. Depending on the relationship between the measurement stability of the sensor and the required ion concentration estimation accuracy, the reference solution need not be measured each time or may not be performed at all.
[0023]
The first embodiment of the present invention uses one type of plus membrane sensor and one type of minus membrane sensor, and corresponds to the case of (1) described above. The measurement target is factory wastewater.
1) A 10 mM (m mol / l) KCl (potassium chloride) solution is prepared as a reference solution. In addition, the same solution as the reference solution is prepared as a reference solution co-washing solution. The reference solution co-wash solution is a solution for washing the reference solution before measuring the reference solution in order to prevent the reference solution from being contaminated with another solution attached to the sensor or the like. The 10 mM (m mol / l) KCl solution is also used as a storage solution to prevent the membrane used in the sensor from drying out.
2) Prepare factory wastewater containing no cyanide ions as a blank sample solution. Moreover, the same liquid as the blank sample liquid is prepared as a co-washing liquid for the blank sample liquid.
3) Prepare a cyan sample standard solution by adding cyanide to the same solution as the blank sample solution to a cyanide ion concentration of 1 ppm. Although the cyanide ion concentration is 1 ppm here, it may be determined appropriately according to the object to be measured. Also, the same solution as the cyan sample standard solution is prepared as a wash solution for the cyan sample standard solution.
4) Select a substance B contained in the same liquid as the blank sample liquid, and the sensor to be used has concentration dependence, add the substance B to the same liquid as the blank sample liquid, and A substance B standard solution in which the concentration difference of substance B is known is prepared. In addition, the same solution as the substance B standard solution is prepared as a co-wash solution for the substance B standard solution. Since there are two sensors used in this embodiment, one type of substance B may be selected. The substance B is preferably a substance having a large influence on the measurement value of the sensor, such as a substance having a large concentration dependency, a substance having a large change in the mixing amount, and the like.
[0024]
5) The reference solution is measured to obtain a measured value Vkb.
In this embodiment, one plus membrane sensor and one minus membrane sensor are used. These sensors are put into and out of the reference solution co-wash solution 2 to 10 times, and after washing, the sensor is immersed in the reference solution to obtain the measured value VkbP of the plus membrane sensor and the measured value VkbM of the minus membrane sensor.
6) The blank sample solution is measured to obtain a measured value Vbs.
Two sensors are put in and out of the wash solution for blank sample solution 2 to 10 times, and after washing, both sensors are immersed in the blank sample solution to obtain measured values VbsP and VbsM of both sensors.
7) Measure the reference solution again to obtain the measured value Vkc.
Both sensors are put in and out of the reference solution co-wash solution 2 to 10 times, and after washing, both sensors are immersed in the reference solution to obtain measured values VkcP and VkcM of both sensors.
8) The cyan sample standard solution is measured to obtain a measured value Vcs.
Both sensors are put in and out of the wash solution for cyan sample standard solution 2 to 10 times, and after washing, both sensors are immersed in the cyan sample standard solution to obtain measured values VcsP and VcsM of both sensors.
9) The reference solution is measured to obtain a measured value Vk.
After putting the sensor in and out of the reference solution co-wash solution 2 to 10 times and washing it together, both sensors are immersed in the reference solution to obtain measured values VkP and VkM of both sensors.
10) The substance B standard solution is measured to obtain a measured value VB.
Both sensors are put in and out of the washing solution for substance B standard solution 2 to 10 times, and after washing, both sensors are immersed in the substance B standard solution to obtain measured values VBP and VBM of both sensors.
[0025]
11) The difference between the measured value Vbs and the measured value Vkb Vbsk = Vbs−Vkb, the difference between the measured value Vcs and the measured value Vkc, Vcsk = Vcs−Vkc, and the difference VBk between the measured value VB and the measured value Vk = VB -Vk is obtained.
Since these are performed for each of the positive membrane sensor and the negative membrane sensor, the difference VbskP = VbsP−VkbP, the difference VcskP = VcsP−VkcP, the difference VBkP = VBP−VkP, the difference VbskM = VbsM−VkbM, the difference VcskM = VcsM−VkcM, and The difference VBkM = VBM-VkM is obtained.
12) Determine a model equation for estimating the concentration of cyanide ions.
Since two sensors are used, the model equation is as follows.
Cyanide ion concentration = a1 Vs1 + a2 Vs2 + c
In order to determine the coefficients a1, a2, and c of this model formula, the values (differences) obtained in 11) are used. An expression is established for each of the liquids described above, and the left side of the expression is the ion concentration of the substance of interest in each liquid. Also, each value (difference) of the plus membrane sensor and minus membrane sensor is substituted for Vs1 and Vs2 on the right side of the equation. In this embodiment,
Cyanide ion concentration 0ppm = a1 VbskP + a2 VbskM + c
Cyanide ion concentration 1ppm = a1 VcskP + a2 VcskM + c
Substance B ion concentration difference ppm = a1 VBkP + a2 VBkM + c
The following three expressions hold. The simultaneous equations are solved to determine the coefficients a1, a2, and c.
[0026]
13) Measure the reference solution to obtain a measured value Vskh.
Both sensors are put in and out of the reference solution co-washing solution 2 to 10 times, and after washing, both sensors are immersed in the reference solution to obtain measured values VskhP and VskhM of both sensors.
14) Measure the sample liquid to be measured and obtain the measured value Vhs.
The same liquid as the sample liquid to be measured is used as a wash solution for the sample liquid to be measured.
Both sensors are put in and out of the wash solution for the sample liquid to be measured 2 to 10 times, and after washing, both sensors are immersed in the sample liquid to be measured, and the measured values VhsP and VhsM of both sensors are obtained.
15) A difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh is obtained.
Since these are performed for each of the plus membrane sensor and the minus membrane sensor, the difference VhskP = VhsP−VskhP and the difference VhskM = VhsM−VskhM are obtained.
16) Substituting each value (difference) obtained in 15) into the model formula determined by each coefficient to estimate the concentration of cyanide ions in the sample liquid to be measured. That is, the concentration of cyanide ions in the sample liquid to be measured is
Cyanide ion concentration = a1 VhskP + a2 VhskM + c
It is estimated to be.
In the present embodiment, each liquid is simultaneously measured by two sensors, but may be measured one by one.
[0027]
The second embodiment of the present invention uses two types of positive membrane sensors, two types of negative membrane sensors, and a conductivity meter. The above-mentioned (10) multiple types of positive membrane sensors, multiple types of negative membrane sensors, This is the case with conductivity meters. The measurement target is factory waste water as in the case of the first embodiment.
1) A 10 mM (m mol / l) KCl (potassium chloride) solution is prepared as a reference solution. In addition, the same solution as the reference solution is prepared as a reference solution co-washing solution.
2) Prepare factory wastewater containing no cyanide ions as a blank sample solution. Moreover, the same liquid as the blank sample liquid is prepared as a co-washing liquid for the blank sample liquid.
3) Prepare a cyan sample standard solution by adding cyanide to the same solution as the blank sample solution to a cyanide ion concentration of 10 ppm. Also, the same solution as the cyan sample standard solution is prepared as a wash solution for the cyan sample standard solution.
4) Select substances B1, B2, and B3 that are contained in the same liquid as the blank sample liquid and whose concentration depends on the sensor to be used, and add the substances B1, B2, and B3 to the same liquid as the blank sample liquid, respectively. Then, a substance B1 standard solution, a substance B2 standard solution, and a substance B3 standard solution whose concentration differences of the substances B1, B2, and B3 from the blank sample liquid are known are prepared. The same solution as the substance B1 standard solution, substance B2 standard solution, and substance B3 standard solution is used as the substance B1 standard solution rinse solution, substance B2 standard solution rinse solution, and substance B3 standard solution rinse solution, respectively. prepare. Since four sensors are used in this embodiment, three types of substance B are selected.
Furthermore, since a conductivity meter is used, a conductivity standard solution in which the conductivity is changed by adding, for example, KCl to the same solution as the blank sample solution is prepared. Then, the same liquid as the conductivity standard solution is prepared as a standard solution co-wash solution.
[0028]
5) The reference solution is measured to obtain a measured value Vkb.
In this embodiment, two plus membrane sensors and two minus membrane sensors are used and a conductivity meter is used. Put these sensors in and out of the reference solution co-wash solution 2-10 times, and after washing, immerse the sensor in the reference solution and measure the two measured values VkbP1 and VkbP2 of the two membrane sensors. The measured values VkbM1 and VkbM2 of the minus membrane sensor and the measured value Vkbd of the conductivity meter are obtained.
6) The blank sample solution is measured to obtain a measured value Vbs.
Put the sensor etc. in and out of the wash solution for the blank sample solution 2-10 times, and after washing, immerse the sensor etc. in the blank sample solution and measure the measured values VbsP1, VbsP2, VbsM1, VbsM2, Vbsd of each sensor etc. Get.
7) Measure the reference solution again to obtain the measured value Vkc.
The sensor or the like is put in and out of the reference solution co-wash solution 2 to 10 times, and after being washed together, it is immersed in the reference solution to obtain measured values VkcP1, VkcP2, VkcM1, VkcM2, and Vkcd of each sensor.
8) The cyan sample standard solution is measured to obtain a measured value Vcs.
Put the sensor, etc. in and out of the wash solution for cyan sample standard solution 2-10 times, and after washing, immerse in the cyan sample standard solution, and measure the measured values VcsP1, VcsP2, VcsM1, VcsM2, Vcsd of each sensor etc. obtain.
[0029]
9-1) The reference solution is measured to obtain a measured value Vk.
The sensor or the like is put in and out of the reference solution co-wash solution 2 to 10 times, and after being washed together, it is immersed in the reference solution to obtain measured values Vk1P1, Vk1P2, Vk1M1, Vk1M2, and Vk1d of each sensor.
10-1) The substance B standard solution is measured to obtain a measured value VB.
Put the sensor, etc. in and out of the washing solution for substance B1 standard solution 2-10 times, rinse it, and then immerse it in substance B1 standard solution. obtain.
9-2) The reference solution is measured to obtain a measured value Vk.
The sensor or the like is put in and out of the reference solution co-wash solution 2 to 10 times, and after being washed together, it is immersed in the reference solution to obtain measured values Vk2P1, Vk2P2, Vk2M1, Vk2M2, and Vk2d of each sensor.
10-2) The substance B standard solution is measured to obtain a measured value VB.
Put the sensor 2-10 times in and out of the washing solution for the substance B2 standard solution, rinse it, and immerse it in the substance B2 standard solution, and measure the measured values VB2P1, VB2P2, VB2M1, VB2M2, VB2d of each sensor etc. obtain.
9-3) The reference solution is measured to obtain a measured value Vk.
The sensor or the like is put in and out of the reference solution co-wash solution 2 to 10 times, and after being washed together, it is immersed in the reference solution to obtain measured values Vk3P1, Vk3P2, Vk3M1, Vk3M2, and Vk3d of each sensor.
10-3) The substance B standard solution is measured to obtain a measured value VB.
Put the sensor, etc. in and out of the washing solution for the substance B3 standard solution 2-10 times, and after washing, submerge in the substance B3 standard solution, and measure the measured values VB3P1, VB3P2, VB3M1, VB3M2, VB3d of each sensor etc. obtain.
9-4) The reference solution is measured to obtain a measured value Vkd.
The sensor or the like is put in and out of the reference solution co-wash solution 2 to 10 times, and after being washed together, it is immersed in the reference solution to obtain measured values VkdP1, VkdP2, VkdM1, VkdM2, and Vkdd of each sensor.
10-4) The substance B standard solution is measured to obtain a measured value Vd.
Put the sensor, etc. into and out of the washing solution for conductivity standard solution 2-10 times, rinse it, and immerse it in the conductivity standard solution, and measure the measured values VdP1, VdP2, VdM1, VdM2, Vdd of each sensor, etc. obtain.
[0030]
11) Difference between the measured value Vbs and the measured value Vkb Vbsk = Vbs−Vkb, difference between the measured value Vcs and the measured value Vkc Vcsk = Vcs−Vkc, difference between the measured value VB and the measured value Vk VBk = VB-Vk (However, in this embodiment, since the standard solutions of substance B1, substance B2, and substance B3 are used, the difference VBk is the difference VBk1 = VB1-Vk1, the difference VBk2 = VB2-Vk2, and the difference VBk3 = VB3. -Vk3) and the difference Vdk = Vd-Vkd between the measured value Vd and the measured value Vkd.
Since these are performed for each of the two plus membrane sensors, the two minus membrane sensors, and the conductivity meter measurement values,
Difference VbskP1 = VbsP1-VkbP1, Difference VcskP1 = VcsP1-VkcP1,
Difference VBk1P1 = VB1P1-Vk1P1, Difference VBk2P1 = VB2P1-Vk2P1,
Difference VBk3P1 = VB3P1-Vk3P1, Difference VdkP1 = VdP1-VkdP1,
Difference VbskP2 = VbsP2-VkbP2, Difference VcskP2 = VcsP2-VkcP2,
Difference VBk1P2 = VB1P2-Vk1P2, Difference VBk2P2 = VB2P2-Vk2P2,
Difference VBk3P2 = VB3P2-Vk3P2, Difference VdkP2 = VdP2-VkdP2,
Difference VbskM1 = VbsM1-VkbM1, difference VcskM1 = VcsM1-VkcM1,
Difference VBk1M1 = VB1M1-Vk1M1, Difference VBk2M1 = VB2M1-Vk2M1,
Difference VBk3M1 = VB3M1-Vk3M1, Difference VdkM1 = VdM1-VkdM1,
Difference VbskM2 = VbsM2-VkbM2, Difference VcskM2 = VcsM2-VkcM2,
Difference VBk1M2 = VB1M2-Vk1M2, Difference VBk2M2 = VB2M2-Vk2M2,
Difference VBk3M2 = VB3M2-Vk3M2, Difference VdkM2 = VdM2-VkdM2,
Difference Vbskd = Vbsd−Vkbd, difference Vcskd = Vcsd−Vkcd,
Difference VBk1d = VB1d-Vk1d, Difference VBk2d = VB2d-Vk2d,
Difference VBk3d = VB3d−Vk3d, Difference Vdkd = Vdd−Vkdd,
Is obtained.
[0031]
12) Determine a model equation for estimating the concentration of cyanide ions.
Since five sensors are used, the model formula is as follows.
Cyanide ion concentration = a1 Vs1 + a2 Vs2 + a3 Vs3 + a4 Vs4 + a5 Vs5 + c
In order to determine the coefficients a1, a2, a3, a4, a5, c of this model formula, the values (differences) obtained in 11) are used. A formula is established for each of the liquids described above, and the left side of the formula is the ion concentration or the like of the substance of interest of each liquid. Also, each value (difference) of the sensor or the like is substituted into Vs1, Vs2, Vs3, Vs4, and Vs5 on the right side of the equation. In this embodiment,
Cyanide ion concentration 0ppm = a1 VbskP1 + a2 VbskP2 + a3 VbskM1 + a4 VbskM2 + a5 Vbskd + c
Cyanide ion concentration 10ppm = a1 VcskP1 + a2 VcskP2 + a3 VcskM1 + a4 VcskM2 + a5 Vcskd + c
Substance B1 Ion concentration difference ppm = a1 VBk1P1 + a2 VBk1P2 + a3 VBk1M1 + a4 VBk1M2 + a5 VBk1d + c
Substance B2 Ion concentration difference ppm = a1 VBk2P1 + a2 VBk2P2 + a3 VBk2M1 + a4 VBk2M2 + a5 VBk2d + c
Substance B3 Ion concentration difference ppm = a1 VBk3P1 + a2 VBk3P2 + a3 VBk3M1 + a4 VBk3M2 + a5 VBk3d + c
Conductivity = a1 VdkP1 + a2 VdkP2 + a3 VdkM1 + a4 VdkM2 + a5 Vdkd + c
The following six formulas stand. The simultaneous equations are solved to determine the coefficients a1, a2, a3, a4, a5 and c.
[0032]
13) Measure the reference solution to obtain a measured value Vskh.
The sensor or the like is put in and out of the reference solution co-washing solution 2 to 10 times, and after washing, is immersed in the reference solution to obtain measured values VskhP1, VskhP2, VskhM1, VskhM2, and Vskhd of each sensor.
14) Measure the sample liquid to be measured and obtain the measured value Vhs.
The same liquid as the sample liquid to be measured is used as a wash solution for the sample liquid to be measured.
The sensor, etc. is put in and out of the wash solution for the sample liquid to be measured 2 to 10 times, rinsed and then immersed in the sample liquid to be measured, and the measured values VhsP1, VhsP2, VhsM1, VhsM2, and Vhsd of each sensor are obtained. obtain.
15) A difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh is obtained.
Since these are performed for two positive membrane sensors, two negative membrane sensors, and the measured values of the conductivity meter, the difference VhskP1 = VhsP1-VskhP1, the difference VhskP2 = VhsP2-VskhP2, the difference VhskM1 = VhsM1-VskhM1, and the difference VhskM2 = VhsM2−VskhM2 and the difference Vhskd = Vhsd−Vskhd is obtained.
16) Substituting each value (difference) obtained in 15) into the model formula determined by each coefficient, and estimating the concentration of cyanide ions in the sample liquid to be measured. That is, the concentration of cyanide ions in the sample liquid to be measured is
Cyanide ion concentration = a1 VhskP1 + a2 VhskP2 + a3 VhskM1 + a4 VhskM2 + a5 Vhskd + c
It is estimated to be.
[0033]
Table 2 shows the correlation between the estimated value of the obtained cyanide ion concentration and the actual concentration, by measuring a solution to be measured having a known cyanide ion concentration using the cyanide ion concentration detection method of the present invention. Indicates the height. The circles in the columns of the plus membrane sensor, minus membrane sensor, and conductivity meter are the sensors used for the measurement.
As can be seen from Table 2, the correlation is quite high.
[0034]
[Table 2]

[0035]
【The invention's effect】
According to the present invention, measurement is performed by combining at least two of a sensor using a plus membrane, a sensor using a minus membrane, and a conductivity meter, preparing an appropriate standard solution, and measuring the standard solution. Since the model equation was calculated using the value and the concentration of cyanide ion was estimated,
It does not require pretreatment of the liquid to be measured as in the analytical method, which is a conventional method for measuring the concentration of cyanide ions, and does not require adjustment of the liquid temperature as in the method using a cyanide ion electrode. It is possible to provide a cyanide ion concentration detection method capable of easily measuring the concentration in a short time.
In addition, if the cyanide ion concentration detection method of the present invention is used, regular monitoring of factory wastewater and the like is facilitated.
[Brief description of the drawings]
FIG. 1 is a flowchart of a cyanide ion concentration detection method according to the present invention.
FIG. 2 is a flowchart of the cyanide ion concentration detection method of the present invention.

Claims (4)

A cyanide ion concentration detection method using a sensor using a film containing an amphiphile,
Preparing a reference solution; and
Preparing a blank sample liquid that is the same type of liquid as the target of cyanide ion concentration detection and that has a substantially 0% cyanide ion concentration;
Preparing a cyan sample standard solution in which cyanide is added to the same kind of liquid as the blank sample solution and the concentration of cyanide ions is known;
Each of the substances B1, B2,..., BN-1 contained in the same kind of liquid as the blank sample liquid and having a concentration dependence of N-1 types, which is one less than the type N of the sensor used. Substance Bi (wherein i is any one of 1, 2,..., N-1) and the concentration of the substance Bi with respect to the blank sample liquid is known. (I = 1, 2, ..., N-1) preparing a standard solution;
Obtaining a measured value Vkb of the reference solution (1);
Obtaining a measured value Vbs of the blank sample solution (2);
Obtaining a measured value Vkc of the reference solution (3);
Obtaining a measured value Vcs of the cyan sample standard solution (4);
The measurement of the reference solution and each measurement of the substance Bi (i = 1, 2,..., N-1) standard solution are alternately performed, and the measured value Vki (i = 1, 2,. .., N-1) and the measured values VBi (i = 1, 2,..., N-1) of the substance Bi (i = 1, 2,..., N-1) standard solution. Obtaining step (5);
Difference Vbsk = Vbs−Vkb between the measured value Vbs and the measured value Vkb, difference Vcsk = Vcs−Vkc between the measured value Vcs and the measured value Vkc, the measured value VBi (i = 1, 2,..., N −1) and the difference between the measured values Vki (i = 1, 2,..., N−1) VBki = VBi−Vki (i = 1, 2,..., N−1) 6) and
The steps (1) to (6) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. Then, a total of N sensors each including one or more sensors each using a membrane having a negative hydrophilic group charge of the amphiphile are obtained, and the difference Vbsk, Vcsk, VBki (i = 1, 2, .., N-1) is used to estimate the cyanide ion concentration. Cyanide ion concentration = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Determining each coefficient a1, a2,..., AN, c of
Obtaining a measured value Vskh of the reference solution (7);
Obtaining a measured value Vhs of the sample liquid to be measured (8);
Obtaining a difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh (9);
The step (7) to the step (9) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. Among the sensors using a membrane having a negative charge on the hydrophilic group of the amphiphile, the sensor used for determining each coefficient of the model formula is used, and the difference Vs1, Vs2, ..., a method of detecting the concentration of cyanide ions, comprising the step of substituting VsN into the model formula determined by each coefficient and estimating the concentration of cyanide ions in the sample liquid to be measured. A cyanide ion concentration detection method using a sensor using a film containing an amphiphile,
Preparing a reference solution; and
Preparing a blank sample liquid that is the same type of liquid as the target of cyanide ion concentration detection and that has a substantially 0% cyanide ion concentration;
Preparing a cyan sample standard solution in which cyanide is added to the same kind of liquid as the blank sample solution and the concentration of cyanide ions is known;
Each of the substances B1, B2,..., BN- contained in the same kind of liquid as the blank sample liquid has concentration dependence depending on the sensor used by N-2, which is one less than the type of sensor used N-1. 2 Each substance Bi (i is any one of 1, 2,..., N-2) standard solution, and the concentration difference of the substance Bi from the blank sample solution is known. Substance Bi (i = 1, 2,..., N-2) standard solution, and the same kind of liquid as the blank sample solution, the conductivity being different from that of the blank sample solution, and the conductivity or blank sample Preparing a conductivity standard solution having a known difference from the conductivity of the solution;
Obtaining a measured value Vkb of the reference solution (1);
Obtaining a measured value Vbs of the blank sample solution (2);
Obtaining a measured value Vkc of the reference solution (3);
Obtaining a measured value Vcs of the cyan sample standard solution (4);
The measurement of the reference solution and each measurement of the substance Bi (i = 1, 2,..., N-2) standard solution and the conductivity standard solution are alternately performed, and the measured value Vki (i = 1, 2,..., N-2) and Vkd and each measured value VBi (i = 1, 2,..., N-2) of the substance Bi (i = 1, 2,..., N-2) standard solution. N-2) and a measured value Vd of the conductivity standard solution (5);
Difference Vbsk = Vbs−Vkb between the measured value Vbs and the measured value Vkb, difference Vcsk = Vcs−Vkc between the measured value Vcs and the measured value Vkc, the measured value VBi (i = 1, 2,..., N -2) and the measured value Vki (i = 1, 2,..., N-2) VBki = VBi-Vki (i = 1, 2,..., N-2) and the measured value Obtaining a difference Vdk = Vd−Vkd between Vd and the measured value Vkd (6);
The steps (1) to (6) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. And a total of N-1 sensors combined with a sensor using a membrane having a negative charge on the hydrophilic group of the amphiphile and a conductivity meter, and the difference Vbsk, Vcsk, Model formula for estimating cyanide ion concentration using VBki (i = 1, 2,..., N−2), Vdk = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Determining each coefficient a1, a2,..., AN, c of
Obtaining a measured value Vskh of the reference solution (7);
Obtaining a measured value Vhs of the sample liquid to be measured (8);
Obtaining a difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh (9);
The step (7) to the step (9) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. The sensor used for determining each coefficient of the model formula among the sensors using the membrane having a negative charge of the hydrophilic group of the amphiphile and the conductivity meter, and the difference obtained for each A method for detecting the concentration of cyanide ions, comprising the step of substituting Vs1, Vs2,..., VsN into the model formula determined by each coefficient and estimating the concentration of cyanide ions in the sample liquid to be measured. A cyanide ion concentration detection method using a sensor using a film containing an amphiphile,
Preparing a reference solution; and
Preparing a blank sample liquid that is the same type of liquid as the target of cyanide ion concentration detection and that has a substantially 0% cyanide ion concentration;
Preparing a cyan sample standard solution in which cyanide is added to the same kind of liquid as the blank sample solution and the concentration of cyanide ions is known;
Each material Bi (i) of each of the substances B1, B2,... BM, whose concentration depends on the M types of sensors used, which are contained in the same kind of liquid as the blank sample liquid. Is any one of 1, 2,..., M) and is a standard solution and has a known concentration difference of the substance Bi from the blank sample liquid (i = 1, 2, ..., M) preparing a standard solution;
Obtaining a measured value Vkb of the reference solution (1);
Obtaining a measured value Vbs of the blank sample solution (2);
Obtaining a measured value Vkc of the reference solution (3);
Obtaining a measured value Vcs of the cyan sample standard solution (4);
The measurement of the reference solution and each measurement of the substance Bi (i = 1, 2,..., M) standard solution are alternately performed, and the measured value Vki (i = 1, 2,. , M) and each measured value VBi (i = 1, 2,..., M) of the substance Bi (i = 1, 2,..., M) standard solution (5);
Difference Vbsk = Vbs−Vkb between the measured value Vbs and the measured value Vkb, difference Vcsk = Vcs−Vkc between the measured value Vcs and the measured value Vkc, the measured value VBi (i = 1, 2,..., M ) And the measured value Vki (i = 1, 2,..., M), VBki = VBi−Vki (i = 1, 2,..., M),
The steps (1) to (6) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. Then, a total of N sensors each including one or more sensors each using a membrane having a negative hydrophilic group charge of the amphiphile are obtained, and the difference Vbsk, Vcsk, VBki (i = 1, 2, , M) is used to estimate the cyanide ion concentration. Cyanide ion concentration = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Determining each coefficient a1, a2,..., AN, c of
Obtaining a measured value Vskh of the reference solution (7);
Obtaining a measured value Vhs of the sample liquid to be measured (8);
Obtaining a difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh (9);
The step (7) to the step (9) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. Among the sensors using a membrane having a negative charge on the hydrophilic group of the amphiphile, the sensor used for determining each coefficient of the model formula is used, and the difference Vs1, Vs2, ..., a method of detecting the concentration of cyanide ions, comprising the step of substituting VsN into the model formula determined by each coefficient and estimating the concentration of cyanide ions in the sample liquid to be measured. A cyanide ion concentration detection method using a sensor using a film containing an amphiphile,
Preparing a reference solution; and
Preparing a blank sample liquid that is the same type of liquid as the target of cyanide ion concentration detection and that has a substantially 0% cyanide ion concentration;
Preparing a cyan sample standard solution in which cyanide is added to the same kind of liquid as the blank sample solution and the concentration of cyanide ions is known;
Each of the substances B1, B2,..., B M of the M types of sensors to be used, which are contained in the same kind of liquid as the blank sample liquid, have concentration dependence depending on the type of sensor used. (I is any one of 1, 2,..., M) The above-mentioned substance Bi (i = 1, 1, which is a standard solution and the concentration difference of the substance Bi from the blank sample liquid is known) 2, ..., M) Standard solution and the same type of liquid as the blank sample solution, and the conductivity is different from the blank sample solution and the difference between the conductivity or the conductivity of the blank sample solution is known. Preparing a conductivity standard solution,
Obtaining a measured value Vkb of the reference solution (1);
Obtaining a measured value Vbs of the blank sample solution (2);
Obtaining a measured value Vkc of the reference solution (3);
Obtaining a measured value Vcs of the cyan sample standard solution (4);
The measurement of the reference solution and each measurement of the substance Bi (i = 1, 2,..., M) standard solution and the conductivity standard solution are alternately performed, and the measured value Vki (i = 1) of the reference solution. , 2,..., M) and Vkd and the measured values VBi (i = 1, 2,..., M) of the substance Bi (i = 1, 2,..., M) and the standard solution. Obtaining a measured value Vd of the conductivity standard solution (5);
Difference Vbsk = Vbs−Vkb between the measured value Vbs and the measured value Vkb, difference Vcsk = Vcs−Vkc between the measured value Vcs and the measured value Vkc, the measured value VBi (i = 1, 2,..., M ) And the measured value Vki (i = 1, 2,..., M), VBki = VBi-Vki (i = 1, 2,..., M) and the measured value Vd and the measured value Vkd. (6) obtaining a difference Vdk = Vd−Vkd from
The steps (1) to (6) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. And a total of N-1 sensors combined with a sensor using a membrane having a negative charge on the hydrophilic group of the amphiphile and a conductivity meter, and the difference Vbsk, Vcsk, Model formula for estimating the concentration of cyanide ion using VBki (i = 1, 2,..., M), Vdk = a1 Vs1 + a2 Vs2 + ... + aN VsN + c
Determining each coefficient a1, a2,..., AN, c of
Obtaining a measured value Vskh of the reference solution (7);
Obtaining a measured value Vhs of the sample liquid to be measured (8);
Obtaining a difference Vhsk = Vhs−Vskh between the measured value Vhs and the measured value Vskh (9);
The step (7) to the step (9) are a film containing an amphiphilic substance, a sensor using a film having a positive hydrophilic group charge of the amphiphilic substance, and a film containing the amphiphilic substance. The sensor used for determining each coefficient of the model formula among the sensors using the membrane having a negative charge of the hydrophilic group of the amphiphile and the conductivity meter, and the difference obtained for each A method for detecting the concentration of cyanide ions, comprising the step of substituting Vs1, Vs2,..., VsN into the model formula determined by each coefficient and estimating the concentration of cyanide ions in the sample liquid to be measured.

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